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Climate change influences the ocean's physical and biogeochemical conditions, causing additional pressures on marine environments and ecosystems, now and in the future. Such changes occur in environments that already today suffer under pressures from, for example, eutrophication, pollution, shipping, and more. We demonstrate how to implement climate change into regional marine spatial planning by introducing data of future temperature, salinity, and sea ice cover from regional ocean climate model projections to an existing cumulative impact model. This makes it possible to assess climate change impact in relation to pre-existing cumulative impact from current human activities. Results indicate that end-of-century projected climate change alone is a threat of the same magnitude as the combination of all current pressures to the marine environment. These findings give marine planners and policymakers forewarning on how future climate change may impact marine ecosystems, across space, emission scenarios, and in relation to other pressures.

Claims for ocean space are growing while marine ecosystems suffer from centuries of insufficient care. Human pressures from runoff, atmospheric emissions, marine pollution, fishing, shipping, military operations and other activities wear on habitats and populations. Ecosystem-based marine spatial planning (MSP) has emerged worldwide as a strategic instrument for handling conflicting spatial claims among competing sectors and the environment. The twofold objective of both boosting the blue economy and protecting the environment is challenging in practice and marine planners need decision support. Cumulative Impact Assessment (CIA) was originally developed to provide an overview of the human imprint on the world's ocean ecosystems. We have now added a scenario component to the CIA model and used it within Swedish ecosystem-based MSP. This has allowed us to project environmental impacts for different planning alternatives throughout the planning process, strengthening the integration of environmental considerations into strategic decision-making. Every MSP decision may entail a local shift of environmental impact, causing positive or negative consequences for ecosystem components. The results from Swedish MSP in the North Sea and Baltic Sea illustrate that MSP certainly has the potential to lower net cumulative environmental impact, both locally and across sea basins, as long as environmental values are rated high and prevailing pressures derive from activities that are part of MSP. By synthesizing innumerous data into comprehensible decision support that informs marine planners of the likely environmental consequences of different options, CIA enables ecosystem-based MSP in practice.

The immense energy potential of the oceans is being increasingly recognized the world over, at the same time the integrity of marine ecosystems is challenged by pressure from multiple human activities. For good reasons environmental licensing procedures are precautionary and new industries must declare their detrimental impacts and provide mitigation measures. New ocean energy industries target renewable energy sources thus, on a grand scale, partly mitigating climate change. However, on-site environmental impacts are yet to be established. In this review we compare ocean energy industries with a wide range of conventional, better understood, human activities and outline environmental risks and research priorities. Results show that ocean energy systems are thought to incur many pressures, some familiar and others with yet unknown effects. Particular uncertainties regard ocean thermal energy conversion (OTEC) and large fast-moving turbines. Ocean energy industries should not be considered in isolation because the significance of environmental impacts depend on the full spectra of human activities in each area. Marine spatial planning provides a platform for holistic assessments and may facilitate the establishment of ocean energy industries, as long as risk-related uncertainties are reduced.

Marine energy technologies can contribute to meeting sustainability challenges, but they are still immature and dependent on public support. This paper employs the Technological Innovation Systems (TIS) framework to analyze the development and diffusion of Swedish marine energy up until 2014. While there were promising device developers, relevant industrial capabilities, and world-class research, the system suffered from weaknesses in several important innovation processes. Finally, the analysis identifies the lack of informed political direction as a critical blocking factor and highlights its connection to domestic market potential.

Fisheries management and sustainability assessment of fisheries more generally have recently expanded their scope from single-species stock assessment to ecosystem-based approaches, aiming to incorporate economic, social and local environmental impacts, while still excluding global-scale environmental impacts. In parallel, Life Cycle Assessment (LCA) has emerged as a widely used and recommended framework to assess environmental impacts of products, including global scale impacts. For over a decade, LCA has been applied to seafood supply chains, leading to new insights into the environmental impact of seafood products. We present insights from seafood LCA research with particular focus on evaluating fisheries management, which strongly influences the environmental impact of seafood products. Further, we suggest tangible ways in which LCA could be taken up in management. By identifying trade-offs, LCA can be a useful decision support tool and avoids problem shifting from one concern (or activity) to another. The integrated, product-based and quantitative perspective brought by LCA could complement existing tools. One example is to follow up fuel use of fishing, as the production and combustion of fuel used dominates overall results for various types of environmental impacts of seafood products, and is also often linked to biological impacts of fishing. Reducing the fuel use of fisheries is therefore effective to reduce overall impacts. Allocating fishing rights based on environmental performance could likewise facilitate the transition to low-impact fisheries. Taking these steps in an open dialogue between fishers, managers, industry, NGOs and consumers would enable more targeted progress towards sustainable fisheries.

The seas of northern Europe are strongly affected by human activities and there is a great need for improved marine conservation. The same region is also the current hotspot for offshore wind power development. Wind farms can have negative environmental impacts during construction, but during the operational phase many organisms are attracted to the foundations and thereby may also find refuge from fisheries. Given the recent implementation of marine spatial planning in Europe and elsewhere, this is a critical time to address potential compatibility and synergies between marine conservation and wind power. This review concludes that offshore wind farms can be at least as effective as existing marine protected areas in terms of creating refuges for benthic habitats, benthos, fish and marine mammals. The degree of advantage for these organisms depends on the location of the wind farm and the level of imposed fishing restriction. Under certain conditions wind farms may even be more efficient means of conservation than ordinary marine protected areas. However, offshore wind farms can be negative for several species of seabirds, essentially as occupying preferred feeding or wintering grounds. In areas important to these seabirds wind farms may not comply with conservation. The results bring important messages to marine spatial planning as some but not all wind farms can be spatially combined with, and even synergistic to, marine conservation.

Offshore wind power is expanding with particular development plans in the Baltic and the North Sea. To reassure an environmentally acceptable development, regulatory authorities need to make informed decisions even when evidence and experience are scarce. In this study Ecological Risk Assessment (ERA) has been applied on a wind farm project in Kattegat, proposed within a spawning ground for the Kattegat cod, a threatened population of Atlantic cod (Gadus morhua L). Six stressors with potential impacts on cod and related to wind farms were investigated. Three of them - extreme noise from pile driving, noise from vessels, and disturbances due to cable-trenching - are related to the construction phase, while lubricant spills and noise from turbines together with electric fields from cables are related to the operation phase. The ecological risk was derived from the combined likelihood and magnitude of potential adverse effects from stressors to the cod population using a weight-of-evidence (WOE) ranking procedure. Available evidence was evaluated based on its reliability, and contradictory arguments were balanced against each other using evidence maps. The option of performing hazardous construction events (e.g. pile-driving) outside biologically sensitive periods was incorporated in the assessment. It was shown that the construction of the wind farm poses a high risk to cod, as defined by the ranked and combined likelihoods and magnitudes of adverse effects. However by avoiding particular construction events during the cod recruitment period ecological risks can be significantly reduced. Specifically for this case, ecological risks are reduced from high to low by avoiding pile-driving from December through June, which confirms previous indications that pile-driving is the most ecologically hazardous activity of offshore wind power development. Additional risk reduction is achieved by avoiding cable trenching from January through May. The study thus illustrates the effectiveness of time-planning for risk reduction. Importantly, the study illustrates how combined ERA and WOE methods can be valuable for handling uncertainties of environmental impacts within offshore industrial development. (C) 2014 Elsevier Ltd. All rights reserved.

Several African countries in the Western Indian Ocean (WIO) endure insufficiencies in the power sector, including both generation and distribution. One important step towards increasing energy security and availability is to intensify the use of renewable energy sources. The access to cost-efficient hydropower is low in coastal and island regions and combinations of different renewable energy sources will play an increasingly important role. In this study the physical preconditions for renewable ocean energy are investigated, considering the specific context of the WIO countries. Global-level resource assessments and oceanographic literature and data have been compiled in an analysis of the match between technology-specific requirements for ocean energy technologies (wave power, ocean thermal energy conversion (OTEC), tidal barrages, tidal current turbines, and ocean current power) and the physical resources in 13 WIO regions Kenya, Seychelles, Northern Tanzania and Zanzibar, Southern Tanzania, Comoros and Mayotte, Northern-, Central-, and Southern Mozambique, Western-, Eastern-, and Southern Madagascar, Reunion, and Mauritius. The results show high potential for wave power over vast coastal stretches in southern parts of the WIO and high potential for OTEC at specific locations in Mozambique, Comoros, Reunion, and Mauritius. The potential for tidal power and ocean current power is more restricted but may be of interest at some locations. The findings are discussed in relation to currently used electricity sources and the potential for solar photovoltaic and wind power. Temporal variations in resource intensity as well as the differences between small-scale and large-scale applications are considered.

A variety of tidal current turbines (TCT) are emerging, the majority focussing on large-scale extraction of renewable energy at global tidal hot-spots. Concurrently, some turbines are small and may be suitable also for micro-scale applications (micro-TCT) in remote areas, such as decentralized electrification in countries where fuel-independent energy systems with high power predictability are particularly important. In shallow waters the force of tidal currents varies considerably over short distances and very site-specific measurements are important for assessment of localization, but are also expensive. For micro-TCT to be of interest site-screening and evaluation must be inexpensive, and low-cost methods are thus required. This study proposes a simplified tidal model that is calibrated to site-specific conditions by short-term observations using lightweight equipment. By measurements comprising down to 8% of the monthly tidal period the potential power output can be estimated, with uncertainty intervals up to ±20%, for currents applicable for micro-TCT. This site-screening method was tested at five sites in Mozambique where near-shore tidal currents were measured with lightweight current meters. At three of the sites, currents were estimated to exceed 1 m s−1 and power output was calculated based on technical assumptions for a micro-TCT device. Results are discussed from the perspective of micro-TCT development and decentralized remote area electrification.

Seagrass grazing is an intrinsic disturbance in primarily tropical and subtropical areas. While there is a general parabolic response in seagrass growth to grazing intensity, there is less knowledge on the role of grazing frequency, as well as potential interactions between grazing intensity and frequency. This study experimentally investigated physiological responses in Thalassia hemprichii to simulated (leaf cutting) grazing regimes with different intensities (25% vs. 75%) and frequencies (1 times vs. 3 times) over 35 days in Chwaka Bay (Zanzibar, Tanzania). The results showed that the two high-intensity treatments (75% removal) had 37–41% lower growth rate than the low-intensity/low-frequency treatment, and rhizome sugar and starch content were both affected in a similar way. A 36% lower starch content in the simulated low-intensity/high-frequency regime (25% × 3) compared to the one of low-intensity/low-frequency (25% × 1) also shows an interaction between grazing intensity and frequency. This suggests that high-intensity (and to some extent frequency) grazing regimes, in comparison to low-intensity regimes, could negatively affect T. hemprichii growth, energy reserves, and thereby the ability to deal with additional stress like light limitation or grazing.

Nitroglycerin (GTN), used in the treatment of ischemic heart disease, acts through the liberation of nitric oxide (NO). However, its clinical use is limited due to tolerance development. Expired NO was used as an indicator of GTN-bioactivation and was measured together with plasma nitrite and mean arterial pressure (MAP) during GTN indicator infusions. The model was applied in rabbits subjected to various time periods of low-dose GTN pretreatment by patch application for 1, 24 and 72 h. Pretreatment with GTN-patch resulted in significant attenuation of expired NO from the GTN indicator infusion in the 24 h and 72 h pretreatment groups compared to placebo (72 h). Dose-response curves with increasing GTN infusions after 24 h GTN-patch pretreatment revealed a significant attenuation of the MAP decrease compared to placebo. GTN-induced changes in plasma nitrite correlated to increases in expired NO and decreases in MAP. This indicates that expired NO could serve as an indicator of NO generation from GTN in the vascular system. We conclude that GTN tolerance is associated with reduced capacity to generate NO from GTN. Care should be taken in using MAP-reduction to evaluate tolerance since high indicator doses could liberate sufficient amounts of NO to elicit maximal MAP decrease even in tolerant animals.

Ensemble classification, in which results from multiple single-scene classifications are combined through a voting procedure, is shown to improve classification accuracy over the classification based on a single best scene. In addition, ensemble classification can produce a complete land cover map in areas without cloud-free remote sensing data. The ensemble classification approach is illustrated with a case study from the shallow-water environment surrounding Inhaca Island, Mozambique (26.0 °S, 32.6 °E), for which 17 Landsat scenes, all from 2013 and containing

Mozambique and Tanzania are countries with very low rural electrification rates – far below 5% percent of the rural population use electricity. The pace of rural grid electrification is slow and for most remote areas access to the national electricity grids will not occur within a foreseeable future. Off-grid (decentralized) electricity grids are seen as a complement and fore-runner to the national grid, making electricity available many years in advance and creating demand and a customer base. Most off-grid systems are supplied by diesel generators which entail unreliable and costly electricity. Alternative off-grid energy sources exist in the region, such as biofuels, wind, micro-hydro and solar PV; but there are significant barriers to adoption, adaptation and diffusion of such RE-based technologies. In this study, the specific drivers and barriers for rural electrification and off-grid solutions in both countries are explored across a stakeholder spectrum. It is part of a larger research effort, undertaken in collaboration between Swedish and African researchers from natural, engineering and social sciences, aiming at an interdisciplinary assessment of the potential for an enhanced utilization of available renewable sources in off-grid solutions. By qualitative methodology, data was collected in semi-structured stakeholder interviews carried out with ten national level energy sector actors. Findings illustrate countryspecific institutional, financial and poverty-related drivers and barriers to grid and off-grid electrification, as perceived by different energy sector stakeholders.

Hydrokinetic turbines, targeting the kinetic energy of fast-flowing currents, are under development with some turbines already deployed at ocean sites around the world. It remains virtually unknown as to how these technologies affect fish, and rotor collisions have been postulated as a major concern. In this study the effects of a vertical axis hydrokinetic rotor with rotational speeds up to 70 rpm were tested on the swimming patterns of naturally occurring fish in a subtropical tidal channel. Fish movements were recorded with and without the rotor in place. Results showed that no fish collided with the rotor and only a few specimens passed through rotor blades. Overall, fish reduced their movements through the area when the rotor was present. This deterrent effect on fish increased with current speed. Fish that passed the rotor avoided the near-field, about 0.3 m from the rotor for benthic reef fish. Large predatory fish were particularly cautious of the rotor and never moved closer than 1.7 m in current speeds above 0.6 ms(-1). The effects of the rotor differed among taxa and feeding guilds and it is suggested that fish boldness and body shape influenced responses. In conclusion, the tested hydrokinetic turbine rotor proved non-hazardous to fish during the investigated conditions. However, the results indicate that arrays comprising multiple turbines may restrict fish movements, particularly for large species, with possible effects on habitat connectivity if migration routes are exploited. Arrays of the investigated turbine type and comparable systems should therefore be designed with gaps of several metres width to allow large fish to pass through. In combination with further research the insights from this study can be used for guiding the design of hydrokinetic turbine arrays where needed, so preventing ecological impacts.